Autotek autocad raster design 2010 用户手册

NOTE The preview reflects the image as it was read from the disk. If you
have made any display-only adjustments to the image using the AutoCAD
IMAGEADJUST command, then those adjustments are not displayed in the
image preview. If you make adjustments to the image using the Histogram,
the adjustments made with IMAGEADJUST are no longer applied to the image;
instead the new settings are applied.

3 Select a channel from which to apply the conversion values. You can

select RGB, or you can select a single channel (Red, Green, or Blue). If
you select RGB, then the values for red, green, and blue pixels in the
image are added together and divided by three to achieve the grayscale
value. If you select one channel, then the Color to Grayscale operation
takes the value for that channel and uses it for the grayscale value.

4 To adjust the scale in the histogram window, move the slider up and

down. Moving the slider up increases the scale such that low frequency
values become more visible and the highest frequency values become
truncated by the top of the window.

5 Select Apply to convert the color image(s) to grayscale.

6 Select Close to exit the Histogram dialog box.

If you are not satisfied with the results, you can use the AutoCAD UNDO
command to restore the original settings.

Menu

Image  ➤  Image Processing  ➤  Histogram

Raster Design Toolbar

Command Line

ihistogram

Dialog Box

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